You also need to consider
* pH corrected ionised calcium (usually the ionised calcium is
corrected to a pH of 7.4).
* collection of samples on ice - stable blood gases but the potassium
increases.
* choice of sample - ionised calcium requires heparin that does not
bind the calcium.
cheers
Trevor Walmsley
"If you need to use statistics then you have done the wrong
experiment"
Trevor Walmsley, Canterbury Health Labs, Christchurch, New Zealand.
Phone: (0064 3) 364 0326 Fax:Phone: (0064 3) 364 0320
eMail: [log in to unmask]
Internet: http://www.cdhb.govt.nz/chlabs/staff/trevorw.htm
>>> Eric Kilpatrick <[log in to unmask]> 27/2/03 11:59 pm
>>>
We are trying to decide whether to add an electrolyte module to our lab
gas analyser, predominantly to be able to measure ionised calcium (we
have an ILyte which can measure Na/K by direct ISE). 2 of our intensive
care/HDU units already have gas instruments which can do this.
Looking into issue it appears that the reference interval for ionised
calcium is often poorly defined for many instruments, so much of the
discrepancy between adj Ca and ionised Ca may be attributable to this
rather than the ionised value being the 'correct' one. There is also the
issue about the when it is appropriate to cascade onto an ionised
measurement. Lastly, I wonder if there is really any requirement for
adding it to our lab instrument when most of the patients who would
benefit from it are probably on the units who already have the
facility.
Any thoughts?
Eric
Dr. Eric S. Kilpatrick
Consultant in Chemical Pathology
Hull Royal Infirmary
Anlaby Rd
Hull HU3 2JZ
Tel: 01482-607708
Fax: 01482-607752
------ACB discussion List Information--------
This is an open discussion list for the academic and clinical
community working in clinical biochemistry.
Please note, archived messages are public and can be viewed
via the internet. Views expressed are those of the individual and
they are responsible for all message content.
ACB Web Site
http://www.acb.org.uk
List Archives
http://www.jiscmail.ac.uk/lists/ACB-CLIN-CHEM-GEN.html
List Instructions (How to leave etc.)
http://www.jiscmail.ac.uk/
**********************************************************************
** This email and attachments have been scanned for content and viruses
and is believed to be clean **
This email or attachments may contain confidential or legally
privileged information intended for the sole use of the addressee(s).
Any use, redistribution, disclosure, or reproduction of this message,
except as intended, is prohibited. If you received this email in error,
please notify the sender and remove all copies of the message,
including any attachments. Any views or opinions expressed in this
email (unless otherwise stated) may not represent those of Canterbury
District Health Board
**********************************************************************
------ACB discussion List Information--------
This is an open discussion list for the academic and clinical
community working in clinical biochemistry.
Please note, archived messages are public and can be viewed
via the internet. Views expressed are those of the individual and
they are responsible for all message content.
ACB Web Site
http://www.acb.org.uk
List Archives
http://www.jiscmail.ac.uk/lists/ACB-CLIN-CHEM-GEN.html
List Instructions (How to leave etc.)
http://www.jiscmail.ac.uk/
|